The present invention relates to a sanitary absorbent product, such as a sanitary napkin or urinary protection article, which is worn in contact with the skin of the wearer for the purpose of absorption and holding of body liquids and, more particularly, to an absorbent product having laterally extending tabs for attachment to the undergarment of the wearer. The tabs feature barrier devices for preventing leakage.
A typical tabbed sanitary napkin includes a central absorbent body, and two or more positioning tabs extending laterally outward from the longitudinal edges of the central absorbent body which are adapted to be wrapped around the edges of the crotch portion of a wearer""s undergarment to hold the sanitary napkin in place. A problem with early designs for sanitary napkins with tabs is that when the tabs are pulled into place, there is a tendency for fluid to wick along the surface of the tabs where it can stain the wearer""s outer clothing since there is no effective barrier against leakage along the side of the napkin. Moreover, when the tabs are pulled into place, the body facing surface of the central absorbent body has a tendency to slope away from the user in the region adjacent the tabs, thus making side leakage more likely to occur in this area.
Various attempts to curb lateral leakage near the tabs have been tried. For example, U.S. Pat. No. 5,391,162 discloses a sanitary napkin with tabs secured in a face-to-face relationship with the back of the napkin. This arrangement allows upstanding barriers to form when the tabs are longitudinally tensioned, the barriers pivoting from their initial flat position to an upstanding position. The deployment of the upstanding barriers depends on accurate placement and correct sizing of the napkin with respect to the user""s undergarment. The fact that the barriers extend substantially along the entire length of the body of the napkin makes the product bulkier and less comfortable. In addition, the correct functioning of this design depends upon accurate installation. In a second embodiment disclosed in the same patent and having similar disadvantages, loops in the non-absorbent layers are provided, running the length of the main body of the napkin, with the main purpose of preventing the flow of liquid into the material in the tabs.
U.S. Pat. No. 5,387,210 suggests an elaborate process of folding the top layer of the tabs whereby side barriers rise when the tabs are folded about the edges of the panty. A disadvantage of this design is that a more complex manufacture process is required. Moreover, a separate piece of material is required to form the top layer of each tab, independent of the top layer of the central absorbent body. Also, unless the fit of the napkin is correct, the side barriers which are supposed to rise may be forced against the skin of the user and be unable to rise when the tabs are pulled.
European patent application published in February 1994 with publication number 0 581 258 A1 discloses a sanitary napkin with positioning tabs. Each tab has an inwardly projecting portion that extends over the cover layer to form a barrier device and an outwardly projecting portion for use in attaching the napkin to the undergarment of the wearer. In manufacture, separate pieces are required for the positioning tabs and the main body, resulting in a more expensive process. Furthermore, as with U.S. Pat. No. 5,387,210, the potential exists for the side barriers to be pressed against the user, and be rendered ineffective.
It is an object of the present invention to provide a sanitary absorbent product with positioning tabs, which obviates or mitigates the aforementioned disadvantages.
It is another object of this invention to provide a novel sanitary absorbent product which provides protection against lateral leakage using barriers which are located and formed in a unique manner so as to simplify manufacture and use.
As embodied and broadly described herein, the present invention provides a sanitary absorbent product comprising a layered elongate main body, said main body having two opposed longitudinal edges, two positioning tabs extending laterally from said main body, each positioning tab having a width and a length, the width being substantially parallel to the longitudinal edges of the main body and the length being substantially perpendicular to the longitudinal edges of the main body. In a preferred embodiment, the width of the tab does not exceed 50% of the length of said main body. Each positioning tab is provided with a side barrier device which projects from a body-facing surface of the positioning tab, said barrier device being integrally formed with the respective positioning tab. It is preferred that the barrier device have a length which does not substantially exceed the width of the tab. Accordingly, the length of the barrier device is substantially shorter than the length of said main body.
In a most preferred embodiment, the sanitary absorbent product is a sanitary napkin that includes an absorbent core held captive between a liquid permeable cover layer and a liquid impervious barrier layer. The cover layer and the barrier layer are provided with co-extensive lateral projections that are peripherally sealed to one another by adhesive or thermal bonding to form the positioning tabs. Optional adhesive zones may be provided on the barrier layer portions of the positioning tabs to allow the tabs to adhere to the garment facing surface of the undergarment of the wearer.
A transverse fold is formed on each positioning tab to provide a barrier function against side leakage. The fold is generally parallel to the longitudinal axis of the sanitary napkin and is located at the interface or juncture of the main body and the positioning tab. In use, when the positioning tab is tensioned and folded around the edge of the panty, the upper surface of the tab (materialized by the lateral projection of the cover layer) acquires a sloping configuration in the region near the boundary of the main body. The fold, however, projects upwardly from the sloping surface and behaves as a barrier, preventing menstrual fluid from escaping and staining the wearer""s clothes. Thus, the ability of the fold to withstand the tension forces exerted on the positioning tab, that cause the tab to incline downwardly, without flattening or otherwise losing its three-dimensional character, substantially reduces the likelihood of failure.
As embodied and broadly described herein, the invention also provides a sanitary absorbent product comprising:
a layered elongate main body, comprising from top layer to bottom layer a cover layer which is permeable to liquid, at least one absorbent layer and a barrier layer which is impermeable to liquid, said main body having two opposed longitudinal edges and two opposed lateral edges;
two positioning tabs extending laterally from said main body intermediate said lateral edges, each positioning tab comprising a barrier layer portion continuous with the barrier layer of said main body, and a cover layer portion continuous with the cover layer of said main body;
an adhesive means provided on the barrier layer portion of each positioning tab for attachment of the tab to a garment facing surface of an undergarment;
the barrier layer portion of each positioning tab being bonded to the cover layer portion of the tab around the perimeter of the tab; and
an upwardly projecting barrier formed along each interface between said positioning tabs and said main body, said upwardly projecting barrier having a length not substantially exceeding a width of a respective positioning tab at said interface, each positioning tab having a maximal width not substantially exceeding 50% of a maximal length of said main body.
As embodied and broadly described herein, the invention also provides a sanitary absorbent product comprising:
an elongate main body, said main body having two opposed longitudinal edges;
a positioning tab extending laterally from each longitudinal side edge of said main body, each positioning tab including:
a) a main tab element extending laterally from a respective longitudinal side of said main body;
b) a secondary tab element projecting from said main tab element from a location thereon that is outwardly removed from a respective longitudinal edge of said main body;
c) an adhesive means provided on said secondary tab element for attachment of the positioning tab to a garment facing surface of an undergarment of a wearer, whereby a region of said main tab element extending beyond said location tends to prevent lateral leakage of liquid exuded by the wearer.
As embodied and broadly described herein, the invention further provides a method of making a sanitary absorbent product, said method comprising the steps of:
providing an absorbent layer having two opposed longitudinal edges and two opposed lateral edges, said absorbent layer having a longitudinal axis;
providing a permeable cover layer and an impermeable barrier layer of substantially the same dimensions, such that said cover layer and said barrier layer possess a main body slightly larger in length and width than said absorbent layer, and two laterally extending positioning tabs, each tab having a maximal width not exceeding substantially 50% of a maximal length of said main body;
sandwiching said absorbent layer between said cover layer and said barrier layer;
bonding said cover layer to said barrier layer along the lateral edges of the main body, and along the perimeter of the positioning tabs; and
folding the positioning tabs to form two upwardly projecting barriers.
As embodied and broadly described herein, the invention also provides a method of making a sanitary absorbent product, said method comprising the steps of:
providing an absorbent layer having two opposed longitudinal edges and two opposed lateral edges, said absorbent layer having a longitudinal axis;
providing a permeable cover layer and an impermeable barrier layer to substantially the same dimensions, such that said cover layer and said barrier layer possess a main body slightly larger in length and width than said absorbent layer, and two laterally extending positioning tabs;
sandwiching said absorbent layer between said cover layer and said barrier layer; and
bonding to each positioning tab a secondary positioning tab along a line of juncture outwardly removed from a longitudinal edge of said main body, said line of juncture extending along said longitudinal edge.